Bootstrap 4 - Navbar Hover Effects

nav.css

.circleBehind a, .brackets a, .pullDown a, .pullUp a, .pullUpDown a
{
    text-decoration: none;
    position: relative;
    z-index: 0;
    cursor: pointer;
}

/* Circle behind */
.circleBehind a:before, .circleBehind a:after
{
    position: absolute;
    top: 20px;
    left: 50%;
    width: 40px;
    height: 40px;
    border: 4px solid lighten($brand-primary, 25%);
    transform: translateX(-50%) translateY(-50%) scale(0.8);
    border-radius: 50%;
    background: transparent;
    content: "";
    opacity: 0;
    transition: all 0.25s;
    z-index: -1;
}

.circleBehind.inverse a:before, .circleBehind.inverse a:after
{
    border: 4px solid $brand-primary;
}

.circleBehind a:after
{
    border-width: 2px;
    transition: all 0.4s;
}

.circleBehind.inverse a:after
{
    border-width: 2px;
}

.circleBehind a:hover:before
{
    opacity: 1;
    transform: translateX(-50%) translateY(-50%) scale(1);
}

.circleBehind a:hover:after
{
    opacity: 1;
    transform: translateX(-50%) translateY(-50%) scale(1.3);
}


/* Brackets go out */
.brackets a:before, .brackets a:after
{
    position: absolute;
    font-size: 1.5em;
    top: 0;
    opacity: 0;
    transition: all 0.25s;
}

.brackets a:before
{
    content: '(';
    left: 0px;
    transform: translateX(10px);
}

.brackets a:after
{
    content: ')';
    right: 0px;
    transform: translateX(-10px);
}

.brackets a:hover:before, .brackets a:hover:after
{
    opacity: 1;
    transform: translateX(0px);
}


.pullDown.inverse a:before, .pullUp.inverse a:before, .pullUpDown.inverse a:before,
.pullDown.inverse a:after, .pullUp.inverse a:after, .pullUpDown.inverse a:after
{
    background: #fff;
}

/* Pull down  */
.pullDown a:before
{
    position: absolute;
    width: 100%;
    height: 2px;
    left: 0px;
    top: -8px;
    content: '';
    background: #999;
    opacity: 0.3;
    transition: all 0.25s;
}

.pullDown a:hover:before
{
    height: 58px;
}

/* Pull up  */
.pullUp a:before
{
    position: absolute;
    width: 100%;
    height: 2px;
    left: 0px;
    bottom: -8px;
    content: '';
    background: #999;
    opacity: 0.3;
    transition: all 0.25s;
}

.pullUp a:hover:before
{
    height: 58px;
}



/* Pull up and down  */
.pullUpDown a:before, .pullUpDown a:after
{
    position: absolute;
    width: 100%;
    height: 2px;
    left: 0px;
    content: '';
    background: #999;
    opacity: 0.3;
    transition: all 0.25s;
}

.pullUpDown a:before
{
    top: -8px;
} 

.pullUpDown a:after
{
    bottom: -8px;
}

.pullUpDown a:hover:before, .pullUpDown a:hover:after
{
    height: 28px;
}

nav.html

<!--
  |--------------------------------------------------------------------------
  | Bootstrap 4 - Navbar Hover Effects
  |--------------------------------------------------------------------------
  |
  | Some options for animating navbar links when hovering over them.
  | Inspired by EvyatarDa (https://codepen.io/EvyatarDa/pen/waKXMd)
  |
  -->

<nav class="navbar navbar-toggleable-md navbar-inverse bg-inverse">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav circleBehind inverse">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<nav class="navbar navbar-toggleable-md navbar-light bg-faded">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav circleBehind">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<br />

<nav class="navbar navbar-toggleable-md navbar-inverse bg-inverse">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav brackets">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<nav class="navbar navbar-toggleable-md navbar-light bg-faded">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav brackets">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<br />

<nav class="navbar navbar-toggleable-md navbar-inverse bg-inverse">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav pullDown inverse">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<nav class="navbar navbar-toggleable-md navbar-light bg-faded">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav pullDown">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<br />

<nav class="navbar navbar-toggleable-md navbar-inverse bg-inverse">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav pullUp inverse">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<nav class="navbar navbar-toggleable-md navbar-light bg-faded">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav pullUp">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<br />

<nav class="navbar navbar-toggleable-md navbar-inverse bg-inverse">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav pullUpDown inverse">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>

<nav class="navbar navbar-toggleable-md navbar-light bg-faded">
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <a class="navbar-brand" href="#">Navbar</a>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav pullUpDown">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
    </ul>
  </div>
</nav>